Assay devices, including detection gels, microfluidic devices, immunoassays, and the like, for detection of an analyte in a sample are known in the art. In particular, lateral flow immunoassay devices are routinely used for detecting the presence of an analyte in a sample. Lateral flow immunoassay devices often use a labeled specific-binding reagent that is releasably immobilized on a test strip of porous material. A liquid sample, such as a biological sample from a human or an environmental sample, is applied to an end of the porous strip and the capillary properties of the strip transports the liquid sample along the strip, releasing the labeled specific binding reagent, which binds specifically to the analyte of interest at a first binding site thereof, if present, in the sample. The labeled binding reagent is then typically captured at a test zone by a second reagent having specific binding for a second binding site of the analyte of interest. Excess labeled binding reagent is captured at a control zone, downstream of the test zone by a control reagent which binds specifically to the labeled reagent.
Commercially available lateral flow assay devices are typically designed to be read by the naked eye of the user or to be read by an instrument. An instrument designed to read a signal emanating from a lateral flow device offers superior sensitivity relative to visually (i.e., naked eye) read devices, as the optical system in an apparatus is able to detect intensities and wavelengths not visible to the naked eye.
A concern with instruments for reading lateral flow devices is the lack of precision, due to inter-instrument and/or operator variability. There remains a need in the art for an apparatus and a system that objectively analyses a signal from an immunoassay test device, where the apparatus has improved sensitivity, accuracy and/or precision for determining the presence or amount of signal from a lateral flow device.
The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the drawings.